With the development of liquid crystal technology, thin film transistor liquid crystal displays (TFT-LCDs), which have high quality, low power consumption and no radiation, have become the mainstream of the market.
In fabrication of a thin film transistor (TFT), in order to avoid an etchant from corroding an area of an active layer corresponding to a channel when etching a source-drain metal between a source electrode and a drain electrode, the following method is generally adopted in the prior art: when removing a first photoresist layer above the active layer, reserving the photoresist above the area corresponding to the channel; then, after a source-drain metal layer is formed, coating a second photoresist layer above the source-drain metal layer, and reserving the photoresist above areas of the source-drain metal layer corresponding to the source electrode and the drain electrode and the photoresist above the area corresponding to the channel so that the reserved photoresist above the active layer can protect the active layer from being corroded when etching the source-drain metal layer; and finally, simultaneously removing the photoresist above the areas of the source-drain metal layer corresponding to the source electrode and the drain electrode, the photoresist in the second photoresist layer above the area corresponding to the channel and the photoresist in the first photoresist layer above the area corresponding to the channel.
This method, however, has one problem as follows: since the photoresist in the first photoresist layer above the active layer is covered by a film layer such as the source-drain metal layer, problems such as incomplete removal of photoresist are apt to occur in the final process of removing the photoresist, which affects characteristics of the TFT.